Related articles

A gene mutation may accelerate the loss of memory in people who are at risk of dementia

Alleles are parts of genes that work in pairs on the chromosomes to determine a person's traits.

People who have a particular version of the BDNF gene experience slightly faster decline in memory and thinking skills

Dr Doug Brown - Alzheimer's Society

The researchers followed 1,023 people with an average age of 55 for up to 13 years who were at risk for Alzheimer's disease but at the start were still healthy.

The participants gave blood samples which were tested for the Met allele gene mutation.

Their memory and thinking skills were evaluated at the start of the study and at each study visit, up to five visits.

GETTY

The researchers followed 1,023 people with an average age of 55 for up to 13 years

Of that group, 140 were also tested with neuroimaging for beta-amyloid, a sticky protein that can build up into plaques found in the brains of people with Alzheimer's.

Almost a third of the participants (32 per cent) had the Met allele.

Researchers found that when compared to people without the gene mutation, those with the mutation lost memory and thinking skills more rapidly.

On tests of verbal learning and memory, those with no gene mutation improved by 0.002 units per year, while the scores of people with the mutation declined by 0.021 units per year.

The researchers also found that people with the gene mutation who also had more beta-amyloid had an even steeper rate of decline.

Study author Doctor Ozioma Okonkwo, of the University of Wisconsin School of Medicine in the US, said: "We found that people with Alzheimer's risk who have this BDNF gene mutation called the Met allele may have a more rapid decline of memory and thinking skills.

"Because this gene can be detected before the symptoms of Alzheimer's start, and because this presymptomatic phase is thought to be a critical period for treatments that could delay or prevent the disease, it could be a great target for early treatments."

Early signs of Dementia

Tue, December 20, 2016

Dementia affects the ability to remember, think and reason. Here are the early signs to look out for in yourself and loved ones.

Researchers found those with the mutation lost memory and thinking skills more rapidly

He added: "When there is no mutation, it is possible the BDNF gene and the protein it produces are better able to be protective, thereby preserving memory and thinking skills.

"This is especially interesting because previous studies have shown that exercise can increase levels of BDNF.

"It is critical for future studies to further investigate the role that the BDNF gene and protein have in beta-amyloid accumulation in the brain."

Dr Okonkwo said a major strength of the study, published online by the journal Neurology, is that it was one of the largest investigating the mutation.

Dr Doug Brown, Director of Research and Development at Alzheimer's Society, said of the findings: "This new research suggests that people who have a particular version of the BDNF gene experience slightly faster decline in memory and thinking skills.

"Around a third of the population have this version of the gene, which is thought to decrease production of the BDNF protein, involved in growth of new brain cells."

He added: "These findings should not be cause for alarm, much more research is needed to see whether the results stand up to scrutiny in larger groups of people.

"However, insights like these could help us better understand what is happening as our brain ages and help to develop new, more personalised, treatments for people with dementia in the future."